Electrical management of potentially lethal arrhythmias has been found to dramatically improve survival rates in candidates at risk of sudden cardiac death. Over 40,000 Implantable cardioverter/defibrillators (ICDs) have been implanted since initial FDA approval in 1985. False positive delivery of shock remains a major problem and newer devices are being designed with more sophisticated arrhythmia detection schemes and tiered- therapy protocols. The goal of this project is to develop a system to standardize testing and device evaluation for future devices. Such a system will assess sensitivity and specificity of detection algorithms and device response to yield reliable statistics on safety and efficacy. In Phase l we will demonstrate the feasibility of designing a standardized test for exercising the arrhythmia detection mechanisms contained within ICDs on a variety of both simulated and clinical experimental data. We will: 1) complete the development of a cardiac simulator of atrial and ventricular events which can mimic any cardiac arrhythmia, and determine device response; 2) create a proprietary test set of clinical data previously recorded during electrophysiology studies, as a companion to an existing training set which has been made available by us to commercial designers of implantable devices; and 3) design a test protocol utilizing both simulated and experimental signals for evaluation of next-generation device performance in such categories as oversensing, undersensing, errors in rhythm diagnosis, errors in pacing therapy and/or shock delivery. The development of an independent testing facility and standardized testing protocol for use by the industry is our goal. PROPOSED COMMERCIAL APPLICATION: The Food and Drug Administration is presently developing performance standards to be applied to future implantable cardioverter/defibrillators submissions for approval. We believe that the establishment of an independent testing facility would facilitate the assessment of comparative device performance and provide valuable safety and efficacy information.